#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>

//getpid()  --获取自己的进程的PID

int main()
{
  
    printf("begin: 我是一个进程，pid: %d, ppid: %d\n",getpid(),getppid());

    sleep(5);
 pid_t id = fork();

 //   printf("我是后续的代码\n");

//   sleep(1);
 // printf("before:only one line\n ");
 //  pid_t id = fork();//创建子进程
    if(id > 0)
    {
         //id就会返回给父进程
         while(1)
         {
           printf("我是父进程,pid :%d,ppid : %d\n",getpid(),getppid());

           sleep(1);

 
         }


    }
    else if(id == 0)
    {
       //id 就会返回给子进程
       while(1)
       {
           printf("我是子进程，pid : %d,ppid : %d\n",getpid(),getppid());

           sleep(1);
       }


    }
    else
    {
       //error

    }


  printf("after:only one line\n ");

 sleep(1);

  while(1)
  {

    printf("I am a process ,my id is: %d,parent: %d\n",getpid(),getppid());

    sleep(1);

   }
    return 0;
}
